Are the "To" and "From" placeholders printed on my Greetabl?

No, they will not be printed on your final Greetabl.

At the moment we do not have an easy way to see a final preview of your message prior to print for customers, but we can send a screenshot to you if you reach out to us through the "HELP" button in the bottom right hand corner of greetabl.com or email your order number to us at hello@greetabl.com.